1. Field of the Invention
The present invention relates to a corporate stop of the type adapted to be installed in the sidewall of a fluid bearing conduit to form a junction or branch and, specifically, to such a stop which is adapted for installation within a lined conduit while the conduit is carrying fluid under pressure.
2. Description of the Prior Art
A variety of circumstances exist in which it is desirable to form a junction or branch line from a main, fluid carrying conduit. For instance, in the municipal area, it is often necessary to install a branch line into a water main, gas or sewer main. A similar need exists in other industries, such as in the chemical pipeline industries.
In the municipal area, many water mains were constructed years ago and the wall structures are now badly eroded or collapsing In order to repair such damage, it has been proposed to insert a liner within these lines to provide a new water-impervious wall to the system. However, the wall of the line, is usually not continuous since branch lines intersect the main line at various entry ports to allow the free flow of fluid from the main to the branch line. In the case of existing and newly formed entry ports, it is desirable to utilize a corporate stop at the junction to control the fluid on either a temporary or permanent basis.
Although a variety of corporate stops are known in the prior art, all suffer from various deficiencies. Many of the prior art assemblies are complicated in design and time consuming to install. In many cases, it was not possible to install the stop on a "live" line which was carrying fluid under pressure. Also, none of the prior art stops of which we are aware were well suited for installation in a conduit which had been previously lined with a synthetic liner.
The present invention has as an object to provide a corporate stop for a fluid carrying conduit which allows blind side installation by drilling a hole straight through the conduit from the exterior.
Another object of the invention is to provide such a stop which seals on both the interior and exterior sidewalls of the fluid carrying conduit.
Another object of the invention is to provide a stop which more securely engages a previously installed synthetic liner within a conduit to eliminate any annular gaps which might be present between the liner and host conduit.
Another object is to provide a stop which provides an enlarged contact area on the exterior of the host conduit for distributing forces generated during installation over a larger area.
Another object of the invention is to provide a sealing element for the corporate stop which is linearly and radially reinforced to resist shear forces during installation and reduce the chances of a blowout during the operational life of the stop.